Written by

Jayne O'Donnell and Kelly Kennedy, USA TODAY

WASHINGTON - Several state- and federal government-run health insurance marketplaces opened Tuesday with glitches, delays and even crashes, marring the launch of the centerpiece of President Obama's health care law.

Some of the delays were due to high volume. President Obama said in a White House conference that more 1 million people tried to use the sites before they officially opened at 8 a.m. ET.

The exchanges are the critical part of the Affordable Care Act's requirement that uninsured Americans buy health insurance. They opened Tuesday for business and the open-enrollment period ...